Mick Christian, regional training and demonstration manager for laundry, at Electrolux Professional, gives us his take on a sustainable future.

For large parts of the past decade, sustainability was at the forefront of all involved within the professional textile care industry.

Undoubtedly, the devastating effects of the COVID-19 pandemic has sharply refocused the thoughts of many, as professionals and businesses alike have had to cope with circumstances unimaginable only a short time ago.

While lockdown measures and social distancing have proved to be immensely challenging for everyone, the reduction of major sources of pollution, such as travel, has also highlighted the true extent of human activity on our environment. As we look to adapt to living through, and we hope, beyond COVID-19, where possible sustainability should remain a major focus for all within the PTC industry.

From a research and development perspective, sustainability has always been a cornerstone of the Electrolux Professional ethos, both in the physical production of a machine, and throughout its operational life. Electrolux Professional’s latest commercial laundry offerings, the Line 6000 commercial washer and heat pump dryer, have been designed to maximise sustainability while keeping utility and running costs to a minimum. For the Line 6000 washers in particular, innovative features such as integrated savings can provide a tangible reduction in an outlets carbon footprint. Unlike traditional systems, the integrated savings system weighs the load in the machine and then dispenses the correct amount of water to suit the weight of the load. As such, the system is able to intuitively reduce water consumption and energy usage when the machine isn’t full to capacity, which can be a huge plus point for operators. Equally, Electrolux Professional’s Line 6000 heat pump dryers have been designed with the intention of not only cut ting energy usage, but delivering a real impact on a site’s bottom line. The built-in heat pump offers energy savings of up to 60 per cent compared to traditional tumble dryers by removing the exhaust, ventilation and water-cooling systems. Additional savings can also be generated via the moisture balance feature, which measures the exact level of moisture throughout the drying process so that the cycle will automatically stop when garments are dry. Not only does this keep costly energy bills down, but it prevents damage to delicate materials.

Mike Edwards, managing director of Innovention Consultancy, discusses the effective use of heat and water.

Few of us are lucky enough to run laundries located on windswept islands, adjacent to a fast flowing freshwater river, or where the sun shines 10 hours a day.

With a combination of solar, wind and hydropower, coupled with boreholes, total water recycling or seawater desalination, we would be able to achieve true sustainability, where the essential resources that we need are being constantly replaced.

Back in the real world this is an impossible dream – our best shot at sustainability is to minimise our primary consumption of water and energy and recycle as much as possible for reuse.

I would like to tackle just one aspect that applies to every laundry, drawing on my company’s four-decade developments and applications as they apply to the waste heat and water that is the result of the process of washing. You may find the conclusion surprising.

The lower the washing temperature, the less energy you use, right? Wrong. Imagine that you currently wash in your CBW at 65°C followed by the standard cold rinse. If you measure the temperature of the mixed wastewater, in a plant processing one tonne of linen per hour the result could be 6,000 litres per hour going to drain at 45°C Essentially you have heated six tonnes of water from the incoming main at 10°C, and then thrown away that same six tonnes at a temperature of 45°C. That’s roughly 243kW in one hour.

Now suppose that you decide to increase your budget for chemicals and introduce a ‘low-temperature washing system’. The wash temperature in the CBW now becomes 50°C and the temperature to drain drops to 35°C. That means that you are now throwing away 173kW per hour, around 28 per cent less than before. The final rinse temperature will also have dropped a few degrees, perhaps to around 23 to 25°C so you can expect the normal production clogging drying times for towelling etc.

Now take the Aquatherm approach, go back to low-cost chemistry but increase the wash temperature to 75°C or higher. The wastewater will now exit the machine at a mixed temperature of around 55°C. Incoming cold freshwater at 10°C is then preheated by the energy extracted from the wastewater, and now feeds into the rinse end of the machine at around 45°C, which with the carryover of heat from the wash section will rise to 50°C prior to pressing/extraction and then drying.

Meanwhile the wastewater, having had its energy largely extracted, will go to the final drain at 20°C or under, a net loss of 70 kW or 71 per cent less than the original process. Any plant study into sustainability must focus on what is being sent to waste, be it through hot water or hot air. What you keep in the building does not need to be replaced; this is the Holy Grail of energy reduction. Meanwhile, with all this recycled heat to play with in the CBW, hot rinsing improves quality, reduces process time and makes significant inroads into drying times. It is not unusual to see fully dried category drying times cut from 20 to 15 minutes, with a corresponding reduction in steam or gas consumption.

This is just one aspect of a complex topic, which when combined with water reuse and carefully matched with suitable chemistry highlights a significant opportunity to change the way that we operate in the laundry industry, to the benefit of the environment and the business itself.

Stephen Pick, of Sermac Ltd, argues that Böwe and sustainability in drycleaning are old friends.

The major costs of processing a drycleaning load is found in energy for distillation and for heating the drying air, be it steam or electricity, and water for cooling.

The easiest way to save on both is to re-use the drycleaning machine cooling water. The water is clean and warm (up to 40°C) and is ideal for feeding to washing machines, so we’d always recommend investing in a holding tank and pump for this purpose.

If re-using the water is not practical the next best option is to re-circulate it and if this is done it is important the water is cooled. Böwe can provide a heat-pump based chiller which can economically remove heat from the cooling water before returning it for re-use. Water consumption with this system is zero.

At the heart of the machine is the drying system. The current Böwe PremiumLine machines use an air-duct developed with the aid of a German aeronautics institute. It is designed to promote smooth air-flow to allow the huge volumes of air to move easily and quietly. More air means better/quicker drying and less energy and water required. Of course, the fan, air heater and heat-pump (fridge) system must also be appropriately sized and this is always the case with a Böwe.

But even the best drying system will waste energy if allowed to continue drying when the garments are already dry. It is for this reason that all the current Böwe machines use a volumetric drying control. This device provides an accurate way to measure the relatively low flow of solvent being recovered towards the end of the drying process.

Accurate drying saves energy, water and time. Also remember garments which are not properly dry when they exit the machine continue to dry on the hanger releasing solvent into the atmosphere causing pollution. As already said, unnecessary drying wastes energy and an example of this is lint stuck inside the cage housing which will require drying during each and every cycle. For many years now the cage housing backplate on a Böwe machine has had a non-stick cataphoresic coating applied. The purpose of this coating is to prevent lint build up.

In 2020 Böwe PremiumLine machines have extended the use of these coatings to include the air-duct and fan housing while the PremiumLine ‘Black Forest Edition’ adds even more coverage including the button trap, another area where a lint build-up would need drying every cycle. Böwe have also designed several features to prevent excessive and inefficient distillation.

More efficient distillation means less energy and water usage and purer solvent. In these days when we are reminded of our vulnerability to infection I would also mention that Böwe have developed a sterilising drycleaning process using a combination of UVA radiation, ozone and a biocide. The process can effectively sterilise at room temperature.

While in the UK perc remains the most popular solvent but, if it were to go, all the Böwe machines we have delivered in the last few years are capable of conversion to MultiSolvent® specification. Some of the newer alternative solvents are delivering very good results in general drycleaning and are definitely worthy of consideration.

For Böwe sustainability is not something we add as an afterthought. It is designed in at the core of each and every one of our machines reducing energy, water and solvent consumption daily for our customers.